I also made these yummy cookies for Desserts & Fireworks and again the recipe came from a Taste of Home magazine.
1-1/4 cups butter, softened
2 cups sugar
2 teaspoons vanilla extract
2 cups all-purpose flour
3/4 cup baking cocoa
1 teaspoon baking soda
1/2 teaspoon salt
2 cups (12 ounces) semisweet chocolate chips
In a large bowl, cream butter and sugar until light and fluffy. Beat in eggs and vanilla. Combine the flour, cocoa, baking soda and salt; gradually add to creamed mixture and mix well. Stir in chocolate chips.
Drop by rounded teaspoonfuls 2 in. apart onto greased baking sheets. Bake at 350° for 8-10 minutes or until set. Cool for 2 minutes before removing from pans to wire racks.